Waterproof construction material



1933. M. E. CAMPBELL 3,394,754

WATERPROOF CONSTRUCTION MATERIAL Filed March 22. 1929 ATTORNEY Patented Jan. $7,. 1933 E. CAMPBELL, 01 LOS ANGELES, CALIFORNIA, ASSIGNOR, BY MESNE ABSIGH HENTS, TO THE FLINTKOTE COBPOBATI RATIO OF MASSACHUSETTS N, 0F BOSTON, MASSACHUSE'ETS, A CORPO- WATEBPROOF CONSTRUCTION MATERIAL Application filed March 22, 1929. Serial No. 349,068.

This invention relates to water roof construction material and to a metho of applying same. More particularly the invention is concerned with the production and industrial application of waterproofing membranes fabricated in the form of sheets of any desired length and width which may be cheaply manufactured and'rapidly appl ed to a surface to be waterproofed, as .by lapping sheets in successive courses with a layer of adhesive substance between the overlapping portions, for bonding the successive courses securely one'to another.

In its more specific aspects, the invention is directed to the production of waterproofing membranes which lend themselves to application with an interposed layer of adhesive waterproofing material in aqueous emulsified form between the successively overlapped portions. The use of aqueous emulsified bitumen as a bonding medium between successive courses of felted sheet material presents numerous advantages over bonding materialheretofore used for this purpose. Thus, where molten necessary to heat the bitumen on the job in order to liquefy it and this procedure is costly and time consuming, as well as dangerous to the workmen, and in fact, during seasons 30 of cold weather, cannot be employed without a great deal of trouble. In order to avoid the necessity of heating bitumen on the job for work of this type, resort has been had to the use of so-called cut-backs, i. e., solutions of the bitumen in volatile solvent such as kerosene or asoline. Here, however, there is involved t e wasteful expense of the solvent which is necessarily lost u on evaporation thereof, and again there is constant danger to the workmen from the inflammability of the solvents. Aqueous emulsions, on the other hand possess the advantages, among others, that they can be applied in the cold; they are relatively cheap to make, and contain no ingredients that render the use of them in any way dangerous. One element or factor however, characterizing bituminous emulsions in various degrees (depending 'upon the nature or constitution of the emulsion), has been more or less generally rebitumen is -used,'it 1s garded as a hindrance to their wide use for purposes such as indicated, and that is the inability of the emulsions to set or coalesce rapidly to a film of suificiently adhesive prop erties to act as an effective bonding medium between adjoinin surfaces. Some emulsions, as for examp e, those made with emulsifying agents of the mineral powder type, do not coalesce to any substantial extent until after they are fairly completely deh drated, and consequently are not suitable wiiere im mediate setting action is required or where only little time for setting is available or permissible. Other types of emulsions, as for example, those made with emulsifying agents such as soap, or the like, are in one respect characterized by their ability to coalesce before dehydration, and hence generally are able to set more quickly than an emulsion of the first named type with the same water content. But even with the emulsions of the second named type, some little time elapses before the coalescence of the dispersed particles has reached a point where a film of the emulsion can be said to exert any substantial bonding action, and hence, for some industrial applications where practically an instantaneous setting action is required, even these emulsions are not entirely satisfactory unless they can be made to set almost immediately after they have been spread out as a film or layer.

The primary object of my invention is to provide waterproof sheets conditioned, in the manufacture thereof, in such a way that when employed in conjunction with aqueous bituminous emulsions, particularly those of the second class above referred to, the film or layer of emulsion applied to the so-conditioned sheets will be caused to set immediately upon being brought into contact therewith.

In accordance with the invention, the sheets are provided on all or part of one or both faces thereof, with a surface covering or layer of a pulverulent substance capable of so affecting a layer of bituminous emulsion which may contact with; the thus covered sheet, that the emulsion'will break and the particles;

thereof coalesce almost instantly. Thus, for

example, where the emulsion is one made with the aid of saponiiied fatty or other oil, the pulverulent surfacing material may he a substance such as hydrated lime, which reacts with the soluble soap emulsifying agent to render the latter insoluble and thus destroy its emulsifying or protecting properties, whereupon the dispersed particles are free, to coalesce and set to a continuous mass.

The invention will be more clearly understood from the following detailed description and illustrative examples, and from the drawing, it being understood, however, that the in vention is notrestricted to the specific examples to be cited, but is susceptible of such variationsas may be comprehended by the subjoined claims. I

In the drawing, the several figures enchillustrate in transverse cross-section, various forms of sheet material embodying the novel features of the invention.

Figure 1 shows a form of sheet in which the pulverulent reactive material is applied to both faces'of the sheet;

Figure 52, shows a form in which the reactive material is applied only to one face of the sheet; i

Figure 3 is a modified structure showing the reactive material applied to thelower face of the sheet, and a layer of crushed mineral surfacing material on the upper face there- Figure t shows a modified form in which the reactive material is applied to a porton of one face of the sheet, the remaining por-' tien of said face being covered with granular m aeral surfacing; and

Figure 5 shows still a further modified in in which the never face is covered with th 1 active material, while the upper face is ad, except for a narrow marginal or age edge, with granular mineral surfacing material.

Referring st to Figure l, the numeral indicates a sheet of felted fibrous material impregnated with a water-resisting material such as asphalt. The felted sheet is prefer ably a sheet of wcli-known'rooling felt made cf-rag, hair, asbestos, orv other fibers, and may i be impregnated in any well-known manner, as

substanti c immersion of the sheet in a bath of molten asphalt, the immersion being followed by a period of cooling to alien/v the satin-ant to be J completely absorbed into the ads and pore '05 of the sheet. After required or desired amount of water "noting saturant has been thus taken up by the sheet, finely divided hydrated lime, gypsum, alum, or the like, is showered or otherwise applied to the surfaces of the sheet and. caused to adhere thereto in a fairly continuous l r indicated at 11 in Figure l, by passi n 'h powder coated sheet are u s. The finely divided mate.

. the surfaces of the siicel, so

applied in successive courses, with .a layer able to preclude the sticking together of successive convolutions thereof when the sheet is rolled for shipment, and in addition, conditions the sheet so that when unrolled-and of soapemulsion of bitumen therebetween, the emulsion will be broken immediately upon contacting with the said finely divided material on the adjoining surfaces of the.

sheet, as a result of the interaction between the hydrated limeor' o'tl'ier'agent composing the finely divided material and the soluble soap emulsifying agent. Upon breaking of the emulsion, and consequent coalescence of the bituminous particles thereof, adhesion of the overlapping portions of the sheets immediately ensues, while the water expressed as a result of the breaking of the emulsion readily drains from the space between the sheets and evaporates. 5

Sheets formed as shown in Figure 1 are admirably suitable for waterproofing subgrades in the construction of roadways and pavements, wherein as established by niodern practice, it is necessary to lay down upon the sub-grade some form of membrane which will preclude the absorption by the sub-grade soil of water from the concrete base applied thereover, since manifestly any loss of water by the concrete will generally prevent complete hydration'and setting thereof to a structure of the required strength. In using the waterproofing sheets of my invention they will generally be applied in successive overlapping courses, each course overlapping the preceding course by approximately twothirds of the width thereof. As each course is laid in place, it maybe sprayed or brushed over the upper two-thirds of its top surface with a soap emulsion of asphalt having a I melting point of say 100200 F., whereupon the above described action between the material of layer 11 and the emulsion will ensue. 'lhe next course is then applied, the coalesced film of asphalt providing the bonding action '110 between the overlapped sheets, the layer 11 on the bottom side of the overlapping course assisting in the coalescence of the film of emulsion it the action of the layer on the top side of the preceding course has not itself developed sufficient coalescence. The i work thus progresses very rapidly, depending only upon the speed at which the successive courses of sheets and interposed layer ofemulsions can be'applied, no time being required on the job for conditioning the materials and no delays being occasioned hy the setting requirements of the bonding medium.

Furthermore, by the use of emulsion as described, the workmen are under no dangers such as attend the use of hot molten asphalt ifianima-ble solvents, and its becomes pos- Y moreover, to carry on the a in e d in warm weather.

constructed as in Figure i suitable for use in providing waterproof roof coverings, by laying them in successively overlapped courses. In the laying of socalled built-up roofs, the sheets of uniform width are arranged in overlapping courses, each sheet lapping the preceding sheet to an extent somewhat in excess of one-half the width thereof. For this use, sheets constructed as shown in Figure 1 may be employed in superposed courses with a layer of soap emulsion of asphalt between the adj oining surfaces, the'settin of which by the action of the finely divided. hydrated lime or similar substance on the opposing surfaces of the sheets being the same as that already described. In laying built-up roofs, it is sometimes the practise to mop the entire surface of the roof covering after the several courses are in place, with a layer of molten asphalt, but here again in accordance with my invention, it is possible to use emulsified asphalt, the setting of which is rapidly induced by the powdered lime, or the like, adhering to the exposed areas of the several courses in the manner already described.

The construction shown in Figure 2 is substantially the same as in Figure 1, with the exce tion that here the pulverulent lime, or the ike, is applied only to one face of the aosheet.

In Figure 3, one face of the sheet is covered as indicated at 11, with the finely divided lime, or similar substance, capable of reacting with soap, while the opposite face thereof 35 is surfaced with a mineral surfacing such as crushed slate, mica, talc, or the like indicated at 12. If desired, also, in this construction a layer or waterproof coating material 13,

such as asphalt, may be applied to the lastnamed face of the sheet prior to the surfacing operation, the crushed slate or other surfacing material being partially embedded in the coating layer. With the construction of Figure 3 the waterproof covering will be applied 5 in successive courses with the face of the sheet carryin the mineral surfacing uppermost, and with a layer of asphalt emulsion between successive courses adapted to be broken by the finely divided lime or the like, on the lowermost face of the lapping courses.

In Figure 4, the sheet 10 impregnated with a waterproofing substance, is provided on one of its surfaces with a layer 14 of waterproof 'coatin material having anular mineral surfacing material 15 partially embedded in a zone longitudinally of the sheet corresponding in width to the exposed width of the sheet, and the remaining ortions of the sheet are provided with an a herent layer 16 of reactive material such as hydrated lime, so that the sheets may be bonded one to another in overlapping courses by the application of a layer of emulsified asphalt over the material 16 of each course immediately prior to 6 laying the next succeeding course in place.

When sheets as shown in Figure 4 are applied on a roof, the crushed mineral 15 on t e exposed areas of the several courses provide a continuous wear and weather resistant surface 4 serving to mask the coating layer 14 from the weathering action of the sun, and also to afford a decorative finish for the roof.

In Figure 5 I have shown a slightl modified construction wherein the layer of granular mineral surfacing 1511 on one face of the sheet is confined to the areas to be exposed so as to leave a more or less smooth selvedge edge 16a, while the opposite face of the sheet carries the layer 17 of hydrated lime or the like. In laying up successive courses of this form, the asphalt emulsion will be a plied to the smooth selvedge areas 16a, and when a succeeding course is laid so as to lap s'aid areas, the material on the bottom face of the succeeding course will come into play and break down the emulsion sufiicientl to cause the lapping portions of the adjoining sheets to be effectively united.

While I have illustrated my invention in connection with soap emulsions of bitumen it is to be understood that other types 0 emulsion may be used, the essential requirement being that the emulsion should comprise such in edients or be of such a degree of stability t at it can be broken down by the action of the pulverulent material applied 2. A waterproof construction comprising a plurality of overlapping sheets of water resistant felted fibrous base having upon at least a portionof a surface of each sheet powdered lime, and upon which bituminous emulsion has been spread during the laying of said sheets.

' Signed at Rutherford, in the county of Bergen and State of New Jersey, this fifth day of March, A. D. 1929.

MAX E. CAMPBELL. 

